Machine for making concrete casings



March 3,1942. l w KELLY 2,275,080

MACHINE FOR MAKING CONCRETE CASINGS y 4o 37 h k i 7 7 3 2 1 9 1 2 9 /4 u; n u /2 26 0 I v Y* L l v 31391 522i" -`L s;-

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MACHINE ECE MAKING CONCRETE CAsINCs Filed 'April 1'7, 1941 5 sheets-sheet 2 Y nventor .W5/Clam .Kelly uw' gttol;

March 3, 1942.

W. KELLY MACHINE FOR MAKING CONCRETE CASINGS Filed April 17, 1941 5 Sheets-Sheet 5 MMM/MW NIN Wamm/Jeezy f C I l Gig@ Patented Mar. 3, 1942 MACHINE FOR MAKING CONCRETE CASINGS William Kelly, Grand Island, Nebr.

Application April 17, 1941, Serial No. 389,057

11 Claims.

This invention relates to improvements in the art of making concrete castings, its more specic purpose being to make either a plain well casing section or a well screen section. This manufacture is accomplished by the centrifugal method which, as herein appears, insures the desired packing or concentration of the concrete and altogether facilitates the making of the sections so that enough of the latter can be produced quickly for a casing string of the required length.

Although the machine is adapted to the manufacture of plain casing sections as suggested above, its primary purpose is to make screen sections because the technicalities involved in the latter are fairly exacting notwithstanding the simplicity of their nature. A screen section requires slots or openings cut or cast through the side of the tube to allow the entrance of water into the Well.

These entrance slots should be narrow on the outside and enlarged or ared toward the inside so that any particle of sand or gravel that may start through a slot may readily pass on into the interior and not lodge inside of the slot where the fact of its obstruction would cause additional clogging and eventual closure of the slot. It is readily seen that if this fault were permitted to be multiplied in any considerable number of entrance slots there would be a serious retardation" and even prevention of the inflow of Water into the well.

In carrying out the purposes of the invention a consideration of utmost importance in the making of a screen section is to make sure of the free entrance of all available ground water. Usually about '7% of the outside of the tube surface is required to be devoted to the slotting for the accommodation .of this Water. It is also a consideration to preserve the strength of the tube, bearing in mind that the screen section which is located at the bottom of the well has superimposed upon it; large numbers of plain casing sections, sometimes enough to carry the casing string to a depth of 200 feet.

The type of slot herein disclosed meets all of the foregoing requirements, it being notable that the slots are formed straight through the concrete and are a contribution both to the copious inflow of water and to the structural strength of the screen section.

With the foregoing preamble in mind the objects of the invention are as follows:

First, to provide a machine for making a screen section in fulllment of the foregoing requirements, the formation of the entrance slots being accomplished as part of the method of driving the concrete against the inner perimeter of the mold cylinder by centrifugal force.

Second, to provide a machine of the character described, employing lemplaceable and removable slotting plates, the contours and cross sectional form of which produce slots of the type desired when the concrete is cast around them.

Third, to provide a screen section making machine wherein the slotting blades which constitute the cores of the slots during the act of casting, are of a separable character to enable their abstraction from the slots in the set screen section.

Fourth, to provide a machine of the character described wherein the mold cylinder is completely separable for the purpose of removing the finished screen section.

Fifth, to provide a screen section for use in a concrete well casing string, said screen section having as its chief attribute a novel type of entrance slot which not only insures a copious inflow of water, but also the structural strength of the screen section.

Other objects and advantages will appear in the following specification, reference being had to the accompanying drawings in which:

Figure l is a plan View of the machine, showing the mold cylinder in place on the power unit, but omitting the two slotting bar assemblages.

Figure 2 is a plan view of the power unit.

Figure 3 is a perspective View of one of the single bar slotting assemblages. v Figure 4 is a perspective View of one of the double bar slotting assemblages.

Figure 5 is a plan View of the mold cylinder, showing the slotting bar assemblages in place.

Figure 6 is a cross section taken on the line 6 6 of Figure 5.

Figure '7 is a detailed view of a portion of one end of the mold cylinder.

Figure 8 is a longitudinal section of a portion of the mold cylinder taken on the line 8 8 of Figure 6.

Figure 9 is a detailed sectional View of the upper left corner of the mold cylinder in Fig. 8.

Figure 10 is a cross section taken on the line Illl0 of Fig. 9.

Figure 11 is a detailed sectional view illustrating one of the anchoring means for the slotting bar assemblages.

Figure l2 is a sectional diagrammatic view i1- lustrating the procedure of abstracting the slotting bars from the mold cylinder and completed concrete casting.

Figure 13 is a perspective View of the finished screen section.

Figure 14 is a detailed View of a portion of the screen section, a part being broken out to illustrate the vertical, inward ilare of the slot.

In carrying out the invention the machine, generally designated l (Fig. l) comprises a rotary mold 2 and a power unit 3, The rotary mold 2 is emplaced upon the power unit 3 (Fig. 1) where it remains largely by gravity, and when it is rotated by the power unit with the required rapidity, the casting of the concrete screen section l! (Fig. 13) is accomplished in the manner herein set forth.

This screen section in itself is an improvement on the patent for Well point, No. 1,256,906, granted to William Kelly Feb. 19, 1919. In that patent the slotting of the casing string was confined to the joints between sections, necessitating the,

making of the latter in one foot lengths, and in turn responding in an undesirably high cost of manufacture. The instant screen section i is manufactured in four foot lengths with the advantage of being able to make it either longer or shorter and of any diametrical size.

It has been pointed out that a great deal of importance rests upon the speciiic type of slot employed` herein (Fig. 14), the virtue of the instant machine being that this slot is capable of beingformed by the centrifugal casting operation of said machine. While on the subject of the slot (Fig. le) it is to be observed that the entrance opening 5 which occurs in the outer wall l of the concrete body l, is long and narrow; the, preferred slot size at this point is 6% inchesby T35 inch. The opening 5 extends inwardly a slight distance at il whereupon at 9 it narrows in the lateral direction and widens slightly in the inward direction, then merges into the main passageway at it). The slot flares in the vertical direction all the way through the cast body as at Il (Fig. 14), ending at the exit opening l2 which measures 3 inches by 1/2 inch.

While the foregoing configuration and measurements are preferred, yet in practice any and, all of the factors can be Varied to suit specic requirements. Another matter of preference which is subject to variation in practice is the distribution of the slots 5 (Fig. 13) in eight circumferentially spaced rows of 23 slots each in a four-foot section. Reverting now to the machine, the power unit 3 (Fig. 2) comprises a heavy oak or other suitable frame i3 which is usually anchored to the floor in some suitable way. This frame incidentally defines a pit Ill which is useful in catching surplus cement and water escaping from the rotary mold 2 during the centrifugal action.

Bearings l5, i6 are secured to alined cross rails of the frame for the respective support of power and idler shafts il, I8. The power shaft il carries a pair of drive rollers i9. The idler shaft i8 carries a pair of idler rollers 25J. The power shaft is coupled at 2i (Fig. 1) with an appropriate prime mover 22, a variable speed device 23 being interposed to enable regulating the speed of rotation of the mold 2.

Said mold is set upon the rollers i9, 2d (Fig. 6). It comprises the mold cylinder 2li which consists of a heavy metal tube. It is made in two halves (Fig. 6), the confronting edges 25 being reinforced by metalstrips 2S which abut each other as shown. The ends of the cylinder lare originally open, but when assembled in the machine are made to abut a pair of end closure rings ill, the radialdimension of which determines the thickness of the body l oi the concrete casting (Figs. 9 to 12).

The mold cylinder 2d is sloted at 28 according to a plan which will produce the rows of slots perfectly plain and a-re vmade in'twoV halves, to,

correspond with theV cylinder 24; One of the splits of each of these bands is shown at 33 (Fig. 8) The innermost bands 39, 3! are spaced from each other and are located in positions immediately of the ends of the cylinder 2d. They are also made in two halves, one of the splits of each of said bands being shown at 35 (Fig. 8).

The ends of the bands til, 3l are connected by pins 35 which are inserted through the knuckles 36 of connecting hinges. These pins are subject to being driven out when the time arrives for disassembling the rotary mold. The two end bands 29, 32, are firmly held in position on the cylinder 2d by having circular tracks Si emplaced upon them. Each of these tracks is internally rabbeted at 38 to contain portions of the bands 2Q, 32. The circular core 39 of each ofA the tracks is occupied by the outer rim of the respective closure ring 2l with a fairly tight nt. Each of the tracks 3l has a flange-59.

Now it can readily be seen that when the rotary mold 2 ismount'ed upon the power unit 3 it remains in place largely by gravity, being cradled between the pairs of driving and idler rollers I9, 2E) (Fig. 6), but inasmuch as the iianges 40 go next to the insides of said rollers it follows that said flanges effectively prevent end motion of the mold 2 during rotation. It is during the latter that the centrifugal casting operation occurs.

Upstanding studs :il are provided in sets of eight on each of the bands 3&1, 3l. These studs are positioned radially (Fig. 6), and when the nuts (l2 on said) studs are screwed home they serve to firmly anchor the respective slotting bar assemblage i3 (Figs. 3 and e). Since each of these assemblages is alike the description of one will suffice for all. The assemblage 43 comprises a pair of slotting bars respectively identied as the single slotting bar lill and the double slotting bar (l5. The reason for the distinction is the structural diierences which are presently made plain.

An angle iron et constitutes the single mount -of a plurality of blades il of the single slotting bar (iii. Each of these blades is winged at 48 to aid in forming the portions 8, 9 of the slot 5 (Fig. le). Thesewings merge into a central lip d., which aids in the formation of the portions lf, I2 of the slot. Said blades are flanged at 59 so as to easily enable aiiixation to the bottom of the iron [lo either by. welding or riveting. Holes 5i accommodate the studs tl and a suflicientv number of. loops 5.2 is provided to provide for the attachment of a hoisting device with which to remove the ysingle slotting bar lil from the completed casting.

A pair of bars 5s (Fig. e) characterizes the double slotting bar d5; These bars are held in spaced relationshipto each other by U-shaped straps 5d, the ends of which are either welded or-riveted to the bars 53-so as to compose a rigid construction. These straps are spaced from each other to -let the blades ill through (Fig. 8) All of the straps 54 are alilr'e with the exception of the pair 55 which aire-made slightly wider than the others. Saidstraps are notched at 56 to t around the studs 4l andto enable a slight lpreliminary-end motion relative to the cylinder 24 in one direction (Fig. l2) in abstracting the double-slotting bar f-ffrorn the'casting l.

Said straps 55'also carry pairsof adjusting screws 5l, the poi-nts ouf-whichV are adapted to rest upon the bands 39'; 3i (Fig. 6)` for regulating the depth to which theblades of theVV assemblage'43 extend into the mold cylinder 2li; The blades Y tions 8, 9 of the slot 5 (Fig. 14).

of the" double slotting bar 45 are designated 58 (Fig. 4). They are winged at 59 and these wings coact with the wings 48 in completing the por- Said wings terminate in central lips 60 which coact with the lips 49 in completing the portions |0`, I2 of said slot. But in order to produce the inward flare I of the slot (Fig. 14), each of the lips 69 is bent at 6| so as to offset the lip 60 from the lip 49 (Fig. 9) when the two slotting bars 44, 45, are set together in the assemblage 43. The blades 58 are hanged at 62 to provide for either welding orriveting to the straps 54.

Rods 63 (Fig. 6) span the longitudinal distance of the rotary mold 2 (Fig. 8) and occupy holes in the closure rings 21, beyond which theyV extend as shown. Clips 64 (Fig. 7) are tted on the extensions, the latter being threaded to take the nuts 65. The clips overlap the circular tracks 31 and when the nuts 65 are driven home the L rings 21, tracks 31 and bands 29, 32, are connected tightly at the ends of the cylinder 24.

The operation Fig. 4, are open on one side so as to rit around the studs 4|.

The single slotting bar 44 is emplaced next. The blades 41 pass through the spaces between the straps 54 and through the remainder of the slots 28 in the cylinder 24, taking positions at the v right of the previously emplaced blades 58 (Figs. 8 and 9). Those parts of the blades 41, 58 now occupying the interior of the cylinder 24 constitute the cores of the slots 5 (Fig. 14) and their interior contours. The blades 41, 58 of the latter of which the offset is a part, constitute a twopart core which is substantially equal in thickness to the least depth of the entrance opening or inlet slot 5. On the same principle the thickness of the slot 28 also substantially corresponds with the least depth of the slot 5. There is thus a fairly tight rit around the two-part core and the latter is necessarily made in two parts; in other Words, has two plates 41, 5B to enable the eventual two-step abstraction of the core. The studs 4| go through the holes 5|, and when the nuts 42 are screwed home the entire assemblage 43 is anchored tightly to the mold cylinder 24.

The adjustment of the screws 51 (Fig. 6) regulate the extent of insertion of the blades 58. The blades 41 are slightly longer than the blades 58 (Fig. 9) but the length is so made that when the single bar 44 is emplaced upon the double bar 45 the ends of the lips 49, 6U, will register. The depth of adjustment by the screws 51 should bring the inner extremities of these lips flush with the interior circumference of the rings 21. It is observed that the closing function of these rings obtains only to the extent of the internal space occupied by the concrete body 1. Otherwise the mold cylinder is internally open.

The mold 2 is now set to rotating and the concrete mix or other desired plastic is placed in the rotating mold, the centrifugal force holding it in place against the interior of the cylinder 24.

Cil

A surplus amount of concrete or plastic is desirably placed into the mold, and While the latter is in rotation a leveling bar is emplaced axially of the mold and is rested upon the inner circumferences of the rings 31 so as to scrape off the surplus and leave the bore of the casting 1 smooth and round.

The mold 2 is then rotated at the proper speed and for a sucient length of time to thoroughly pack the concrete around the slotting blades 41, 58, as well as to drive out all surplus moisture. The inner edges of the lips 49, 69, will just show on the interior of the casting 1. To remove the latter from the mold it is first necessary to unscrew the nuts 42 from the studs 4|. The single slotting bar 44 is then pulled straight out (arrow a, Fig. 12). The slotting bar 45 is then pulled by giving it an initial end motion to dislodge the offset lips 6|) from the iiare of the slot, and then straight out (arrow b, Fig. l2). The loops 52 are used in hoisting the bar 44, but after this bar is removed it is relatively easy to lift the bar 45.

After assemblages 44 and 45 are removed, mold 2 is picked up by a suitable hoisting gear and raised clear of rollers |9 and 29 (Fig. 2), circular tracks 31 are removed, mold 2 with its casting 1 is then stood on end resting on end enclosure 21, nuts 65 are removed from bottom ends of rods 63 which are then removed thru top enclosure ring 21, top enclosure ring 21 is lifted off the top, pins 35 (Fig. 6) are drivenA out of the four hinges 36 and the two halves of mold 2 are then opened up, casting `1 is left standing on lower enclosure ring 21 until cured, when casting 1 can be removed from enclosure ring 21.

The holes left in the body 1 by the removal of the rods 63 are eventually used for the threading through of cables or long rods to holdthe screen section 4 in line with superimposed casing sections.

ll. claim:

1. A casting machine for producing an inwardly flared entr-ance opening in a moldable substance, said machine comprising a container having a space for the substance in -plastic form, said container having at least one slot which conforms substantially to the dimensions of the entrance opening, and a core lling the slot and extending into the substance-space, said core including an outwardly bent lip to form the flare and being of plural parts to enable progressive abstraction of the parts through said slot from the entrance opening when the substance has set.

2. A casting machine for producing an inwardly flared entrance opening in a moldable substance, said machine comprising a cylinder having an internally peripheral space for the substance in plastic form, said cylinder having at least one slot which is in substantial correspondence with the dimensions of the entrance opening, and a core filling the slot and extending into the substancespace, said core including an outwardlybent lip stantial correspondence with the dimensions of the entrance opening, and a core filling the slot and extending into the substance-space, said core consisting of a pair of blades laid face to face, one of the blades being offset from the other to form the flare and both blades being separately maneuverable through the slot both into and out of position in said space.

fl. A casting machine for producing an inwardly flared entrance opening in a moldable substance, said machine comprising a cylinder having an internally peripheral space for the substance in plastic form, said cylinder having at least one slot which is in substantial ycorrespondence with the dimensions of the entrance opening, means to rotate the cylinder thus to employ centrifugal force in driving the plastic s-ubstance outwardly into said space, and a core filling the slot to plug it against any material escape of the solids of said substance, extending into the space for the packing of the substance therearound, said core having twin blades one of which is straight and the other offset to define the aforesaid are, said blades being separately movable in abstracting the core from the devious form of the opening.

5. A casting machine comprising a mold having at least one slot and an internal space for the occupancy of a moldable substance, means with which to form in said substance an entrance opening enlarging inwardly of said substance from the size of the slots, said means consisting of a pair of blades extending through the slot into the internal space, a pair of bars to which the blades are individually attached, and means by which the bars are anchored to the mold in superimposed positions, supporting said blades in filling positions in said slot and in core position in s-aid space.

6. A casting machine comprising `a mold having at least one slot and an internal space for the occupancy of a moldable substance, means with which to form in said substance an entrance opening enlarging inwardly of said substance from the size of the slot, said means comprising a core having a `portion substantially filling the slot and another portion occupying the space in core position, a pair of blades which compose the core, one of the blades being oifset from the other to form said inward enlargement, bars to which the respective blades are attached, being separately maneuverable both for the introduction of said offset into and back through the slot,

and means by which said bars are anchored on the mold in superimpos-ition upon each other, thus to support the core.

7. A casting machine comprising a mold having a row of slots and an internal space for the occupancy of a moldable substance, means with which to form in said substance a row of entrance openings in conformity with the slots, each of said openings enlarging inwardly of said s-ubstance from the size of the respective slot, said means consisting of a plurality of straight blades to form one side of each opening and a plurality of offset blades to form the flared sides ol' the openings, a bar carrying all of the straight blades, a double bar having spaced straps carrying the oset blades, and means for anchoring the respective bars to the mold and to each other in superimposed positions with the straight blades extending through the spaces between the straps closely beside the oiset blades in occupancy therewith of the slots in suspended positions in said space.

8. A, casting machine comprising a mold having at least one slot andan internal space for the occupancy of a moldable substance, means with which to form in said substance an entrance opening enlarging inwardly of said substance from the size of the slot, said means consisting of a support having a straight blade and another support having lan offset blade, said supports having openings, and studs on the mold upon which said supports are tted at the openings and secured in superimposition with said means eX- tending through the slot into said space, one of said openings being elongated to allow endwise movement of the respective support in abstracting the offset blade from the substance when set.

9. A casting machine comprising a mold having a row of slots and an internal space for the occupancy of a moldable substance adjacent to the row, closures for the ends of said space extending inwardly of the mold only a fractional distance thereof, means for rotating the mold thus to centrifug-ally drive said substance outwardly in the mold into said space, cores occupying the slots and extending into the space, each of said cores consisting of companion blades at least one of which is offset to form a slot of devious shape in said substance, a pair of bars 'by the respective ones of which the blades of each kind are carried, means to anchor the bars together and to the mold, and means carried by at least one of the bars to rest against the mold and limit 'the extension of the cores to a line on a level with the inner limits of said end closures thus to allow striking off surplus volumes of the substance during the rotation of the mold.

10. A centrifugal casting machine comprising a power unit including confronting pairs of rollers, and means for driving at least one of the pairs of rollers, an entirely separate rotary mold emplaceable upon the power unit, said mold including a cylinder having tracks rested on the rollers in cradled positions between the pairs thereof thus to remain in place by gravity but be subject to rotation by the action of the rollers, cores carried by said mold, extending to the inside of the cylinder for the `formation of slots in a moldable substance driven to the inner periphery of the cylinder by its rotation, and closure rings for the ends of the cylinder being of a radial dimension equal to that of the depth of inward eX- tension of the cores thus to allow the application of a straight edge through the open center of the mold for striking off surplus volumes of the substance during rotation.

ll. In. a centrifugal casting machine, a rotary mold including a longitudinally halved cylinder, a plurality of circular bands for the cylinder, all of said lbands being halved and two of the bands being located at the respective ends ofthe cylinder, :circular tracks at said ends of the cylinder being fitted over the respective bands to hold them together, separable hinge connections for the ends of another one of said bands encircling the cylinder medially of its ends, closure rings separably combined with the tracks, and rods situated longitudinally of the cylinder, being affixed to the closure rings to hold them tightly against the ends of the cylinder.

WILLIAM KELLY. 

